This invention relates to a laminated tube utilized for producing a fishing rod, a golf club shaft, or the like and a method of manufacturing the laminated tube.
In a known art of this technical field, a laminated tube for producing a fishing rod or golf club shaft, for example, has been prepared in such manner that a prepreg sheet is formed by impregnating, with a thermosetting and thermoplastic resin solution, an organic or inorganic fiber cloth or an organic or inorganic fiber uni-directional sheet of high strength and high modulus property such as glass fiber or carbon fiber, the prepreg sheet is wound around a mandrel and then subjected to heat hardening treatment to thereby prepare a hollow cylindrical member, and an amorphous metallic tape is wound around the outer periphery of the thus formed hollow cylindrical member in spiral form (as disclosed in the Japanese Utility Model Laid-open Publication No. 60-88727). Furthermore, in the described prior art, an amorphous metallic wire may be disposed in a winding fashion in the interposed layer of the hollow cylindrical member.
However, in the prior art described above, the amorphous metallic tape and the amorphous wire have less adhesive property with respect to the hollow cylindrical prepreg of epoxy resin. For this reason, in case of the amorphous metallic tape wound around the outer periphery of the hollow cylindrical member, the amorphous metallic tape is easily come up due to repeated bending load applied to the cylindrical member and, hence, is easily peeled off. In the case of the amorphous wire wound between the intermediate layers of the hollow cylindrical member, a reinforcing fiber may be broken due to the winding tension of the wire because of a round cross section of the wire and the intermediate layers may be peeled off from each other due to the repeated bending load of the hollow cylindrical member. The progress of the peeling phenomenon causes formation of a gap between the intermediate layers, resulting in the significant lowering of the buckling strength of the formed cylindrical member.
In order to obviate the defects described above, the applicant of this application has proposed a method of preparing a liminated tube in which a metallic foil tape made of such an amorphous material is formed as a cloth tape woven with fibers having high strength and high modulus property such as carbon or glass fiber, the thus formed cloth tape is wound around a laminated tube body formed by winding a fiber reinforced prepreg sheet, and the thus formed laminated tube is then subjected to the heat hardening treatment.
The proposed method may substantially obviate the defects of the peeling of the metallic foil tape and the inter-peeling of the intermediate layers, but involves problems of additional processes such as weaving process and prepreg preparing process, which results in increased costs of a final product.